// Copyright (c) 2023, ETH Zurich and UNC Chapel Hill.
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#pragma once

#include "colmap/util/eigen_alignment.h"
#include "colmap/util/types.h"

#include <Eigen/Core>

namespace colmap {

// 2D point class corresponds to a feature in an image. It may or may not have a
// corresponding 3D point if it is part of a triangulated track.
struct Point2D {
  // The image coordinates in pixels, starting at upper left corner with 0.
  Eigen::Vector2d xy = Eigen::Vector2d::Zero();

  // The identifier of the 3D point. If the 2D point is not part of a 3D point
  // track the identifier is `kInvalidPoint3DId` and `HasPoint3D() = false`.
  point3D_t point3D_id = kInvalidPoint3DId;

  // Determin whether the 2D point observes a 3D point.
  inline bool HasPoint3D() const { return point3D_id != kInvalidPoint3DId; }
};

}  // namespace colmap
